تفاعل #349524

معادلة التفاعل

end product

8-Chloro-5,6-dihydro-4-oxo-6-phenyl-4H-pyrazolo[1,5-a][1,4]benzodiazepine-2-carboxaldehyde

EtOH

hydrazine-hydrate

→

8-Chloro-2-methyl-5,6-dihydro-4-oxo-6-phenyl-4H-pyrazolo[1,5-a][1,4]benzodiazepine

المذيبات

THF hexane

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe reaction was heated
2. 2
   درجة الحرارةto reflux for 17 hours
3. 3
   درجة الحرارةcooled
4. 4
   تركيزconcentrated in vacuo
5. 5
   workup.ADDITIONpotassium t-butoxide added
6. 6
   درجة الحرارةthe mixture heated
7. 7
   درجة الحرارةto reflux for 8 hours
8. 8
   workup.ADDITIONThe reaction was poured over ice and brine and toluene
9. 9
   workup.ADDITIONadded
10. 10
    أخرىThe toluene phase was separated
11. 11
    تجفيفdried over Na2SO4
12. 12
    استخلاصThe aqueous phase was extracted well with CH2Cl2
13. 13
    تجفيفthe combined extracts dried over Na2SO4
14. 14
    تركيزconcentrated
15. 15
    أخرىthe crude product recrystallized from THF/hexane
16. 16
    أخرىto give the desired end product, mp 258°-261°
17. 17
    أخرىwas obtained as colorless crystals

الإجراء التجريبي

To a solution of 3.43 g. (10.15 mmol) of the end product of Example 15 in 60 ml. of absolute EtOH, was added 12 ml. of hydrazine-hydrate. The reaction was heated to reflux for 17 hours, then cooled and concentrated in vacuo. The residue was taken up in 60 ml. toluene; 1.0 g. potassium t-butoxide added and the mixture heated to reflux for 8 hours, then cooled to room temperature and stirred for 9 hours. The reaction was poured over ice and brine and toluene added. The toluene phase was separated and dried over Na2SO4. The aqueous phase was extracted well with CH2Cl2 and the combined extracts dried over Na2SO4. The dried solutions were combined and concentrated and the crude product recrystallized from THF/hexane to give the desired end product, mp 258°-261°. An analytical sample was prepared by an additional recrystallization from THF/hexane and was obtained as colorless crystals: mp 259°-261°.

المصدر